Convert your DC motor into a dynamo and use it to generate light without batteries. All you need is some capacitors, a DC motor, diode, wire, gear system and LED. To make it light all you need to do is spin your dynamo.

Step #1:

Step #2:

Now we are going to build the "battery system" using capacitors. By connecting the capacitors in parallel (not series), we can hold more charge by using any combination of capacitance and quantity of capacitors. Generally, for the electrolytic capacitors used here, size matters. The bigger the capacitor the more charge it can hold. The capacity of every capacitor along with its unit of measure is marked on its case. Most common electrolytic capacitors are measured in microfarads (μF or MFD).

To make the "battery," solder all the negative pins of the capacitors together. Solder this to a length of wire.

Solder all the positive leads of the capacitors together then solder this to a length of wire.